@Tami253
There are two service fee structures for hosts, they are explained here:
https://www.airbnb.com/help/article/1857/what-are-airbnb-service-fees
Usually they can be choosen in your account, section "payments/payouts", tab "service fee"
In the "split-service fee structure" the guest is charged the "Airbnb Guest Service fee" (+ VAT if applicable). The low percentage is used on "long term stays" (28 nights and more), the high percentage is used for shorter stays.